Tobacco rod forming method and device



United States Patent [72] Inventor Athos Cristiani e w Italy '{21 Appl. No. 742,931 [22] Filed July 5, 1968 [45] Patented Dec. 22, 1970 [73] Assignee American Machine 8: Foundry Company a corporation of New Jersey [32] Priority July 21, 1967, Feb. 27, 1968 [33] Italy [31 1 Nos. 7l77A/67 and 6844A/68 [54] TOBACCO ROD FORMING METHOD AND DEVICE 12 Claims, 7 Drawing Figs. [52] 11.8. 131/84, 131/110 [51] int. Cl. A24c 5/18 [50] Field ofSearch 131/84, 84B, 84C, 110, NDA, 111B, 21D; 198/29, 32

[56] References Cited UNITED STATES PATENTS 589,121 8/1897 Carper 131/84 71 1,639 10/1902 Merkert 131/84 1,755,080 131/110 4/1930 Schunemann Primary Examiner-Joseph S. Reich Attorneys-George W. Price and Eli Weiss, Esq.

ABSTRACT: A relatively wide and thin CAr etBFmBaEOLA I ticles is fed onto an exposed surface of a moving air-permeable conveyor. Suction is applied to the unexposed surface of the conveyor, the unexposed surface being in juxtaposition with an impervious stationary supporting member having a Y- shaped cutout arranged so that the arms of the Y converge in a downstream direction. A similar Y-shaped cover is similarly placed above the conveyor in the region of the cutout and is spaced from and parallel with the exposed surface of the conveyor so that air passing through tobacco and the air-penneable conveyor due to said suction, will cause the edges of the carpet of tobacco particles to converge in a downstream direction thereby forming a relatively narrow, thick and elongated tobacco rod stream.

SOURCE OF SUCTION PATENTEUBEEZZISYB 3548x337 sum 1 [1F 4 IN VI'JN'I'OR.

ATHOS CRISTIANI BY PATENTEU [H22 1970 SHEU 2 OF 4 ATT NEY PATENIED BEBE 2197!] mvmv'rme. ATHOS CRISTIANI (f/4&7

ATTO NEY PATENTEH nc22 19m sum u BF 4 IN VI'JN'I'UIL ATHOS CRISTIANI ATTORNEY TOBACCO ROD FORMING METHOD AND DEVICE The present invention relates to cigarette and cigar making machines and in particular to a method and apparatus for the formation of a tobacco rod therein. 9

Notwithstanding advances made in cigarette making devices, the feeding and arranging of the cut tobacco particles themselves into a continuous rod or braid, sufficiently uniform and regular, for wrapping has not been adequately improved to permit desired high-speed operation. Generally, the presently known devices for manufacturing cigarettes have been limited to a production rate of about 2,000 cigarettes per minute because of the inability to feed the cut tobacco particles at higher rates.

It is theprimary object of this invention to provide a method for feeding cut tobacco particles to a cigarette making machine at high speeds and with uniform regularity so as to produce a tobacco rod having a relatively uniform density.

It is another object of this invention to provide a method and an apparatus for forming a tobacco rodhaving a'determinable density and volume.

These objects, advantages and features, as well as others, will be apparent and obvious from the following description which is to be taken as nonrestrictive examples of the method and apparatus. In the description reference is made to the attached drawings wherein: I

FIG. 1 is a perspective view with parts broken away of a cigarette rod or braid forming device employing a substantially endless belt supporting surface in accordance with the principles of this invention;

FIG. 2 is a perspective view of the device according to FIG. 1, without the belt, in order to show the suction means arranged under the belt;

FIG. 3 shows a perspective view and, in an enlarged scale, a detail of the device according to FIGS. 1 and 2;

FIG. 4 is a plan view of the tobacco rod formation according to FIGS. 1 and 3; v f

FIG. 5 is a perspective view with parts broken away of a device in accordance with the principles of this invention employing a rotary drum supporting surface;

FIG. 6 is a schematic sectional view of a cigarette making machine according to the present invention, employing a rotary drum, rod forming means; and g i FIG. 7 is a perspective view partially in section of a rotary drum support in accordance with the principles of this invention and employed in the machine of FIG. 6. Y

The method of the present invention can best be described in connectionwith certain basic structural elements; therefore, reference is now made to FIGS. 1 4 where a simple embodiment is shown comprising a substantially flat, endless, airpermeable belt for receiving cut tobacco particles. The belt 1 is tightly stretched and mounted about a pair of spaced pulleys 2 and 3. Conventional motor and drive means are employed to drive at least one of the pulleys, namely, the rear pulley 3, in a uniform but adjustable speed so that the belt is driven in the direction of arrow A. The belt 1 is composed of a lower support portion or layer 101 which is perforated with relatively large holes and an upper, closely woven layer 201 which is adapted to receive the tobacco particles.

The belt 1 is mounted for complete support on a substantially hollow, rectangular frame 5 to which is connected, by means of a manifold 6, a suction fan or blower through which air may be withdrawn from beneath the belt 1. The top wall 105, of frame 5, is provided with an opening 7 having a shape substantially that of an isosceles triangle whose base 107 extends transversely to the longitudinal axis of the belt 1 or frame 5, and substantially over its width. The sides 207 of the opening 7 converge along the direction of movement of belt 1 and join into a longitudinal slot 8 extending the remaining length of the frame 5, thus extending the opening 7 along the axis of the direction of movement.

The belt 1, frame 5, opening 7 and slot 8 may be varied in dimension and size by means of a mask or the like depending upon the amount of tobacco fed to the supporting surface, the rate at which the tobacco is fed, the width of the supporting surface, the speed at which the surface is moved, the amount of suction applied and the dimension of the triangular-shaped opening. No single factor is critical and each is somewhat dependent upon the others and readily determinable by those in the art. For simplicity, it may be preferred to provide a single structure of fixed physical dimensions and to obtain control of the density and size of the resultant rod or braid by adjustment of and control of the more easily handled variable factors such as the rate of feed and belt speed and the amount of applied suction. The various alternatives should be readily apparent to those in the art. I

Mounted above and spaced from the belt 1 is a Y-shaped covering 9. The covering 9 acts as a guide for both tobacco and airflow and is substantially parallel to the surface of the belt 1. his oriented with its stem 109 forward in the direction of motion 4 of belt 1 above the axial slot 8 and with its branches 209 extending above and along the converging edges 207 of the opening 7. The width of branches 209 and of stem 109 of the Y-shaped guide is such that they extend beyond the peripheral edges of the slot 8 and of opening 7. The vertical distance at which the cover is mounted above is made variable by suitable means for example as by adjusting screw 10 with respect to mounting bracket 11 and by adjustable bracket 12 by which the cover is secured to the frame 5.

Tobacco particles are fed and distributed on to belt 1 as schematically illustrated by arrows B in FIG. I in a uniform thin layer without lumps or knots as seen in FIG. 4. Belt 1 continuously moves in the direction of arrow A and carries the uniform layer of tobacco 14 above the open section 7 of the frame 5 where it is acted upon by the vacuum created therein by action of the suction blower. While the belt 1 moves between the opposed open section 7 of the frame 5 and the correspondingly Y-shaped cover 9, the tobacco particles condense or collect transversely of the direction of movement of the belt and progressively along lines corresponding to the edges of the branch 209 of the cover 9 and edges 207 of the opening 7. For illustration, this convergence may be likened to the formation of a pair of converging elements 215 along the edges of the triangular section defined by the opening 7.

The convergence or collection of the tobacco into the elements 215 is determined pneumatically by virtue of the airflow through the belt 1. The air drawn through the belt 1 and the opening 7 passes at least partially in the direction of arrows 16 from the lateral area outside the triangular section defined by the opening 7 and thus tends to carry the tobacco resting laterally beyond the cover 9 and not directly effected by the air flow through the opening 7 transversely and angularly into the area defined by the same opening. Since the central portion of the belt is covered by tobacco particles, the suction merely holds such tobacco particles in place thereon as seen in FIG. 4, even though moving forwardly with the belt. The cover 9 aids in this transverse movement. The air drawn from above the belt by the vacuum passes through the space between cover 9 and belt 1 giving rise to the air currents de y picted by arrows 116. Because of the forward movement of the belt 1, the air current has a slight component in the direction of arrow A laterally of the edges 207.

The tobacco layer is thus progressively and continuously gathered together into the two semibraid portions 215 extending along the edges 207 under the respective branches 209 and assumes a Y-shaped configuration. The elements 215 converge at the apex of opening 7 to fonn a single tobacco braid 15 along the imaginary axis corresponding to the slotted opening 8 extending from opening 7. Air currents under the stern 109 of the cover are substantially similar to the currents under branches 209 causing the formation of a single braid 15. It is to be noted that the movement of the supporting surface and the action of the air currents on the tobacco acts to roll and intertwine the cut tobacco particles into a uniform, regular density braid but having a heterogeneous mixture of stranded, cut tobacco particles.

In the embodiment just described, the elements 215, as well as the completed single braid 15, are condensed and collected as a result of the airflow created by the vacuum through the supporting surface and the pneumatic flow created by the movement of the surface. The suction beneath the belt creates the air current following lines 16 and 116 flowing from either side of the Y-shaped guide, into the space between the guide and the belt substantially transverse to the axis and parallel to the surface of the belt. These air currents are distributed along the length of the supporting surface creating the rolling and the intertwining of the particles. Thus, the size and condition of the tobacco particles are of little importance. Large strands, square pieces, and fines (i.e., dust) are all intertwined and interwoven in the completed braid. A uniform, regular rod or braid of fixed density may thus be obtained by the practice of the present invention with only minimal regard to the type of tobacco, its cut, etc.

Having completely formed a tobacco braid 15 as indicated at the terminus of the Y-guide, it may conveniently be transferred for wrapping within a paper or tobacco sheet overwrapper so as to form a cigarette. The braid 15 may therefore be delivered to a rod former of a conventional type as will be apparent.

Turning now to FIG. 5, there is shown a second embodiment for the braid forming device comprising a cylindrical drum 51 instead of the endless belt 1 as a supporting surface. The drum, supported about its central axis, is adapted to rotate in the direction of arrow 54 and is air-permeable having an inner perforated supporting surface 151 and an outer surface 251 of closely woven net or closely perforated outer metal.

' A suction manifold 55 arranged within and fixed to the inside wall of the drum 51 is connected by means of a connecting mechanism 56 to suitable source of suction (not shown in FIG. but similar to that shown in FIG. 1). The manifold box 55 (which corresponds to the frame 5 shown in FIGS. 1-4) has an outer wall adjacent the inner surface of the drum 51 in which there is formed a triangular opening (corresponding to the opening 7 of FIG. l-4). About and spaced from drum 51 is fixed a Y-shaped covering 59 (corresponding to covering 9 of FIGS. 1-4) which is curved to conform to the curvature of the drum 5]. The covering 59 is adjustably secured to a housing member 50 by means of a slot and screw arrangement or the like so that it may be adjustably positioned a predetermined distance from the surface of 251 of the drum as desired. The two branches 259 of the Y-shaped covering extend along the converging edges of the triangular opening in the manifold box 55 in substantially the same manner as described in connection with the corresponding elements of FIGS. l-4. Es-

sentially the embodiment of FIG. 5 is the same as that of FIGS. 14 except that the endless belt having a substantially flat run is replaced by a rotating drum having a curved surface and curved direction of movement. In operation, cut tobacco particles are fed to the rotating drum to form a thin layer thereon in that portion of the drum between or preceding the widest divergence of arms 259. The layer of tobacco deposited on the drum is collected and converged as previously described being first converted into two tobacco semibraids and subsequently into a single braid'along the lines established by the cooperating triangular opening beneath the surface of the drum and the Y,-shaped covering above the surface. The air currents which determine the tobacco collection and convergence are indicated by the arrows 116 in FIG. 5 since they correspond substantially to those currents depicted in FIGS. 1-4. The tobacco braid exiting from drum 5] at the terminus of stem 159 of the covering 59 is a sufficiently formed, uniform braid of heterogeneously arranged tobacco particles (i.e., cut tobacco,

fines, dust, etc.)-and may be transferred to a cigarette making machine by any conventional means as indicated previously.

eference can now be'made to FIGS. 6 and 7 wherein a novel combined cigarette maker employing the braid forming mechanism is shown. The cigarette maker according to the inverition comprises an infeed hopper 61 into which cut tobacco particles are conveyed by suitable delivery means (not illustrat'ed). A carding drum or roller 62 of carding unit (62, 63)

66. Roller 62 cooperates with a counterrotating carding drum' 63 continuously cleaned by cleaning roller 64. A separate picker roller 65 releases the carded tobacco particles from the roller 62 dropping it to the belt conveyor'66 consequently delivering the cut tobacco T to a rod or braid forming device similar to that shown in FIG. 5. The tobacco delivering and carding apparatus is generally similar to that well known in the art and details of its construction are therefore not given.

The braid forming device comprises a drum 67 rotating in the direction of arrow F7 around its substantially horizontal axis. This drum is made! air-permeable and has a preferably perforated surface and has its interior set to communicate with a hollow axial extension connected to a suitable suction source. A fixed section chamber 69 (see FIG. 7) preferably arcuate, is located within drum 67. The chamber 69 is adjacent to the inner wall of drum surface 167 of the drum 7 and is connected by means of a pipe 68 to the suitable source of suction such as a blower or vacuum chamber of the type seen in FIG. 1. The chamber 69 has in its peripheral portion 169 a triangular suction opening 269 from the apex of which extends forwardly in the direction of rotation of drum 67 into a suction slot substantially similar as described in FIGS. l-5.

About drum 67 and at a predetermined distance from it there is mounted a Y-shaped covering element 70 which is so curved as to be substantially parallel to the cylindrical surface 167 of the drum. The cover 70 has two branches which extend along the converging edges of the triangular suction opening 269 and a single stem 270 extending along at least part of the extended suction slot provided in the chamber 69.

Drum 67 is integrally connected with toothed wheel 71 by means of which it is caused to rotate by an actuating device such as a motor with suitable connections (not illustrated). Suction chamber 69 is integral with a sleeve 72 equipped with a perforated flange 73 by which the whole device can be mounted on the machine framework not shown. Thus sleeve 72 comprises both the rotation trunnion or bearing for toothed wheel 71 and for rotating drum 67 as well as the means for maintaining the suction chamber 69 in fixed position. Sleeve 72 can connect chamber 69 directly to the source of suction eliminating the pipe 68 if desired. The surface 167 of cylinder 67 generally comprises a perforated plate covered by a wire net 74 and, as in the operation of the device of FIG. 5, cut tobacco particles are fed directly on wire net 74. This is accomplished by belt 66 moving in the direction of drum 67 so that the cut tobacco particles will then be transferred through suction applied through the drum 67.

The tobacco particles transferred from belt 66 will be caused to adhere on wire net 74 in the form of a very thin layer or carpet since that is the way it is delivered to the belt 66. Drum 67 rotates in the direction of arrow F7 so that the tobacco layer is conveyed in the area between the edges or sides 369 of the triangular opening 269. The tobacco spread on wire net 74 gathers transversely of the direction of movement, progressively forming two elements, converging in the direction of rotation of cylinder 67 substantially along the converging edges 369. This gathering of the tobacco particles along these lines, under the respective branches 170 of. Y- shaped covering 70 is determined pneumatically by the action of the air sucked in chamber 69 through air-permeable wire net 74 and surface 167 in the manner previously described in detail with regard to corresponding parts shown in FIGS. 1- 5. The outside air is drawn through wire net 74 in the area of converging edges 369 and in the area of all the extensions of this opening, passing at least partially from the outside of the triangular area towards the inside through the hollow space between wire net 74 and converging branches 170 of the overlying Y-shaped covering. Air currents are thus generated which flow over the outer surface of cylinder 67 and inwardly from the sides towards each branch 170, thus collecting under these branches the tobacco layer which, prior to being moved to them, was distributed uniformly on wire net 74. Two elements converging under the stem 270 are thus formed. These two elements are formed into a single tobacco braid 84 in the area of extending stem 270 of Y-shaped covering.

a In this invention the movement of drum 67, i.e., the supporting surface for the tobacco, can be operated at a rather high speed. Consequently, as a result of the rotation of drum 67, the tobacco particles, sucked up to it from the conveyor 66 undergo a transformation and a separation action during which the heavier particles such as stems and birds eyes are removed from the bulk of the tobacco as indicated by the present processing and braid formation.

. Of course, the amount of separation will vary with the speed of drum 67, its radius of curvature and other factors obvious to those in the art. At the end of stem 270 and a little farther from the point in which suction through wire net 74 is shut off, the single braid 84 is transferred to a tobacco compressor wheel 75 which rotates in the direction of arrow F8, counter to that of braid forming device 67. The transfer is preferably by suction so that the braid is continued to be positively carried in the same form, shape and uniformity as made on drum 67. The wheel 75 consists of an air-permeable drum 76 within which can be formed and maintained a certain vacuum, for example, by coupling the inside of the'drum to a suitable suction source (not illustrated) through axial duct 77. An airpermeable conveying belt 78 is applied to the drum, guided by rollers 79 to extend to and be in line with the inlet of rod forming mechanism 80. The belt 78 is guided between two raised sides 81, the distance between which corresponds to the width of the'tobacco braid which is transferred from the braid forming drum 67 to the tobacco compressor wheel 7 51A member 82 is provided within the drum 75 to shut off suction through a portion .of the surface 78 along an arc in which the surface of the drum 75 is not used in conveying.

A trimmer 83 is located tangentially to the tobacco compressor. wheel v75 to trim excess tobacco from the braid 84. The excess tobacco is returned to the hopper by means of a conveyor 85. Trimming is preferable only under certain circumstances and is here shown only to depict the versatility of the present mechanism. The braid 84 is then transferred by belt 78 to a rod forming line 80. At the rod former, the braid is laid on a continuous paper tape 86 which is held and guided by an endless belt 87. The paper tape is folded, wrapped and passed through conventional rod forming devices such as paster, dryer and cutoff to form a completed cigarette. An acco'mpanying belt 88 may be used to transfer the braid 84 undisturbed from the tobacco compressor wheel to the rod forming device'if desired.

While this invention has been shown and described in the best forms known, it will nevertheless be understood that these are'purely exemplary and that modifications may be made without departing from the spirit and scope of the invention:

I claim:

1. In the manufacture of cigarettes and cigars, a method of forming a rod oftcut tobaccoparticles comprising the steps of forming a relatively thin andwide carpet of tobacco particles on a first side of an air-permeable supporting surface, moving said air-permeable supporting surface continuously in a predetermined direction, applying suction to a second side of said air-permeable supporting surface, directing airflow in a pattern through said air-permeable supporting surface to pneumaticallydrive the edgesyof the thin layer of tobacco laterally and transversely of said pathqin a progressively decreasing'form and converging into a narrow path along an axis parallel to said path of movement'to form a relatively narrow, thick and elongated single stream of tobacco. Y

2. Apparatus for forming a rod of tobacco particles comprising an air-permeable supporting surface, means for moving said air-permeable supporting surface in a predetermined direction, means for forming a carpetof tobacco particles on said surface, a source of suction coupled to draw air through said air-permeable supporting surface, and wall means having a shaped cutout interposed between said source of section and said air-permeable supporting surface defining a pattern of airflow through said air-permeable supporting surface for pneumatically moving the edges of said tobacco carpet toward each other and converging the same into a single elongated stream of tobacco with the movement of said surface.

3. A rod forming device for a cigarette-or cigarmaking machine comprising a hopper for cut tobacco particles, a carding unit for removing a selected amount of tobacco particles from said hopper, a drum having an air-permeable peripheral surface for receiving said removed tobacco from said carding unit, said carding unit being adapted to deliver said tobacco particles in a substantially thin carpet on said surface, drive means coupled to rotate said drum in a predetermined direction, a vacuum chamber positioned within said drum having a triangular shaped passageway communicating with the air-permeable peripheral surface of said drum, the base of said triangular-shaped passageway being oriented substantially parallel to the axis of rotation of the drum and its sides converging along the direction of rotation of the drum, an impermeable cover mounted above and spaced from the peripheral surface of the drum to direct airflow around and between said cover and drum, and a source of suction coupled to said vacuum chamber to progressively collect the carpet of tobacco on said peripheral surface in a substantially triangular pattern thereby forming said tobacco into a single elongated stream of tobacco particles.

4. The apparatus according to claim 3 wherein said cover is shaped to conform to the triangular passageway.

5. The apparatus according to claim4 wherein said cover is Y-shaped and has arm portions which are aligned with the converging sides of the triangular-shaped passageway.

6. Apparatus for forming a rod of tobacco particles comprising an air-permeable surface for receiving tobacco particles, means for moving said surface in a predetermined direction, a fixed frame mounted beneath said surface having an opening therein defining an angular pattern the vertex of which extends in the direction of movement of said surface and also defining an elongated slot, an impermeable cover mounted above and spaced from said air-permeable surface to direct air currents over said air-permeable surface and through said tobacco in predetermined directions, and suction means connected to said opening for withdrawing air through said air-permeable surface whereby tobacco particles deposited on said surface converge along the pattern defined by saidopening into a single stream on movement of said sur- I face and application of said suction.

7. The'apparatus according to claim 6 wherein said cover conforms to a pattern corresponding to that defined by said opening.

8. The method of claim 1 including spacing a covering from the first side of said air-permeable supporting surface along a portion of the pattern of airflow through said airpermeable supporting surface.

9. The method of claim 1 wherein said step of directing a pattern of airflow through said air-permeable support surface comprises providing a V-shaped pattern converging in the direction of motion of said air-permeable supporting surface.

l0.-The method of claim 1 wherein said step of directing a pattern of airflow through said air-permeable support surface comprises providing a Y-shaped pattern having arm portions which converge in-the direction of motion of said air-perrneable supporting surface.

11. The structure of claim 2 including acovering positioned 12. The structure of claim 11 wherein said shaped cutout above the tobacco carpet on said surface and aligned with a comprises a perimeter having two edges converging in the portion of the perimeter of said shaped cutout in said wall direction of motion of said air-permeable supporting surface. means. 

